The field of the present invention relates generally to turbine engines and, more particularly, to combustor assemblies for use in turbine engines.
At least some known turbine engines, such as gas turbine engines, use cooling air to cool a combustion system used within the engine. Often the cooling air is supplied from a compressor coupled in flow communication upstream from the combustion system. More specifically, in at least some known turbine engines, cooling air is discharged from the compressor into a plenum that extends at least partially around a transition piece of a combustor assembly. A portion of cooling air entering the plenum is supplied to an impingement sleeve that circumscribes the transition piece, prior to the cooling air being channeled into a channel defined between the impingement sleeve and the transition piece. Cooling air entering the cooling channel is then discharged downstream into a second channel defined between a combustor liner and a flowsleeve.
Any remaining cooling air entering the plenum is channeled through inlets defined within the flowsleeve prior to being discharged downstream into the second channel. Cooling air flowing through the second channel cools an exterior portion of the combustor liner. Providing cooling air to a combustor liner is necessary during operation of the turbine engine, as the liner may operate within one of the highest temperatures as compared to other turbine engine components. More specifically, to prevent thermal differential stresses, it is important to cool the entire combustor liner. However, providing cooling air to an aft end of a combustor liner may be difficult, as the aft end is generally radially inward of an interface of the combustor liner and the transition piece. The inability to effectively cool the aft end of the combustor liner may result in thermal cracking, thermal differential stresses, and/or damage to the combustor liner, all of which may reduce the overall useful life of the combustor liner and/or increase the cost of maintaining and operating the turbine engine.